commit: 8f536c47fddf4a9fe15b969b888f4dbd22c1f82a Author: Sergei Trofimovich <slyfox <AT> gentoo <DOT> org> AuthorDate: Thu Apr 4 07:00:23 2019 +0000 Commit: Sergei Trofimovich <slyfox <AT> gentoo <DOT> org> CommitDate: Thu Apr 4 07:00:23 2019 +0000 URL: https://gitweb.gentoo.org/proj/gcc-patches.git/commit/?id=8f536c47
8.3.0: backport retpoline/jumptable optimization on i386 Reported-by: Thomas Deutschmann Bug: https://gcc.gnu.org/PR86952 Bug: https://bugs.gentoo.org/682218 Signed-off-by: Sergei Trofimovich <slyfox <AT> gentoo.org> .../28_all_i386_retpoline-and-jumptable.patch | 64 ++++++++++++++++++++++ 8.3.0/gentoo/README.history | 1 + 2 files changed, 65 insertions(+) diff --git a/8.3.0/gentoo/28_all_i386_retpoline-and-jumptable.patch b/8.3.0/gentoo/28_all_i386_retpoline-and-jumptable.patch new file mode 100644 index 0000000..64e9528 --- /dev/null +++ b/8.3.0/gentoo/28_all_i386_retpoline-and-jumptable.patch @@ -0,0 +1,64 @@ +https://gcc.gnu.org/PR86952 +https://bugs.gentoo.org/682218 + +From 4fa11b10fc05a132b68b6df198706a97c3f4d61e Mon Sep 17 00:00:00 2001 +From: marxin <marxin@138bc75d-0d04-0410-961f-82ee72b054a4> +Date: Mon, 11 Mar 2019 09:38:06 +0000 +Subject: [PATCH] Backport r269492 + +2019-03-11 Martin Liska <mli...@suse.cz> + + Backport from mainline + 2019-03-08 Martin Liska <mli...@suse.cz> + + PR target/86952 + * config/i386/i386.c (ix86_option_override_internal): Disable + jump tables when retpolines are used. +2019-03-11 Martin Liska <mli...@suse.cz> + + Backport from mainline + 2019-03-08 Martin Liska <mli...@suse.cz> + + PR target/86952 + * gcc.target/i386/indirect-thunk-7.c: Use jump tables to match + scanned pattern. + * gcc.target/i386/indirect-thunk-inline-7.c: Likewise. + + +git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gcc-8-branch@269572 138bc75d-0d04-0410-961f-82ee72b054a4 +--- a/gcc/config/i386/i386.c ++++ b/gcc/config/i386/i386.c +@@ -4958,6 +4958,12 @@ ix86_option_override_internal (bool main_args_p, + opts->x_param_values, + opts_set->x_param_values); + ++ /* PR86952: jump table usage with retpolines is slow. ++ The PR provides some numbers about the slowness. */ ++ if (ix86_indirect_branch != indirect_branch_keep ++ && !opts_set->x_flag_jump_tables) ++ opts->x_flag_jump_tables = 0; ++ + return true; + } + +--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-7.c ++++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-7.c +@@ -1,5 +1,5 @@ + /* { dg-do compile } */ +-/* { dg-options "-O2 -mno-indirect-branch-register -mfunction-return=keep -mindirect-branch=thunk -fno-pic" } */ ++/* { dg-options "-O2 -mno-indirect-branch-register -mfunction-return=keep -mindirect-branch=thunk -fno-pic -fjump-tables" } */ + + void func0 (void); + void func1 (void); +--- a/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-7.c ++++ b/gcc/testsuite/gcc.target/i386/indirect-thunk-inline-7.c +@@ -1,5 +1,5 @@ + /* { dg-do compile } */ +-/* { dg-options "-O2 -mno-indirect-branch-register -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic" } */ ++/* { dg-options "-O2 -mno-indirect-branch-register -mfunction-return=keep -mindirect-branch=thunk-inline -fno-pic -fjump-tables" } */ + + void func0 (void); + void func1 (void); +-- +2.21.0 + diff --git a/8.3.0/gentoo/README.history b/8.3.0/gentoo/README.history index 1a755db..2e14fb3 100644 --- a/8.3.0/gentoo/README.history +++ b/8.3.0/gentoo/README.history @@ -1,6 +1,7 @@ 1.1 TODO + 26_all_overridable_native.patch + 27_all_flto-make-all.patch + + 28_all_i386_retpoline-and-jumptable.patch 1.0 22 Feb 2019 + 01_all_default-fortify-source.patch
